Abstract

Adaptive optics (AO) imaging methods allow the histological characteristics of retinal cell mosaics, such as photoreceptors and retinal pigment epithelium (RPE) cells, to be studied in vivo. The high-resolution images obtained with ophthalmic AO imaging devices are rich with information that is difficult and/or tedious to quantify using manual methods. Thus, robust, automated analysis tools that can provide reproducible quantitative information about the cellular mosaics under examination are required. Automated algorithms have been developed to detect the position of individual photoreceptor cells; however, most of these methods are not well suited for characterizing the RPE mosaic. We have developed an algorithm for RPE cell segmentation and show its performance here on simulated and real fluorescence AO images of the RPE mosaic. Algorithm performance was compared to manual cell identification and yielded better than 91% correspondence. This method can be used to segment RPE cells for morphometric analysis of the RPE mosaic and speed the analysis of both healthy and diseased RPE mosaics.

© 2013 Optical Society of America

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2013 (4)

2012 (2)

2011 (4)

2010 (1)

2008 (3)

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

J. Carroll, S. S. Choi, and D. R. Williams, “In vivo imaging of the photoreceptor mosaic of a rod monochromat,” Vis. Res. 48, 2564–2568 (2008).
[CrossRef]

J. I. W. Morgan, A. Dubra, R. Wolfe, W. H. Merigan, and D. R. Williams, “In vivo autofluorescence imaging of the human and macaque retinal pigment epithelial cell mosaic,” Investig. Ophthalmol. Vis. Sci. 50, 1350–1359 (2008).
[CrossRef]

2007 (3)

2006 (1)

2005 (1)

O. Strauss, “The retinal pigment epithelium in visual function,” Physiol. Rev. 85, 845–881 (2005).
[CrossRef]

2002 (3)

A. Roorda, F. Romero-Borja, I. William Donnelly, H. Queener, T. Hebert, and M. Campbell, “Adaptive optics scanning laser ophthalmoscopy,” Opt. Express 10, 405–412 (2002).
[CrossRef]

L. V. Del Priore, Y.-H. Kuo, and T. H. Tezel, “Age-related changes in human RPE cell density and apoptosis proportion in situ,” Investig. Ophthalmol. Vis. Sci. 43, 3312–3318 (2002).

D. M. Snodderly, M. M. Sandstrom, I. Y.-F. Leung, C. L. Zucker, and M. Neuringer, “Retinal pigment epithelial cell distribution in central retina of rhesus monkeys,” Investig. Ophthalmol. Vis. Sci. 43, 2815–2818 (2002).

2001 (1)

M. Boulton and P. Dayhaw-Barker, “The role of the retinal pigment epithelium: topographical variation and ageing changes,” Eye 15, 384–389 (2001).
[CrossRef]

1997 (1)

1996 (1)

D. T. Miller, D. R. Williams, G. M. Morris, and J. Liang, “Images of cone photoreceptors in the living human eye,” Vis. Res. 36, 1067–1079 (1996).
[CrossRef]

1995 (1)

L.-K. Huang and M.-J. J. Wang, “Image thresholding by minimizing the measures of fuzziness,” Pattern Recogn. 28, 41–51 (1995).
[CrossRef]

1993 (1)

D. Bok, “The retinal pigment epithelium: a versatile partner in vision,” J. Cell Sci., Suppl. 17, 189–195 (1993).

1989 (1)

C. K. Dorey, G. Wu, D. Ebenstein, A. Garsd, and J. J. Weiter, “Cell loss in the aging retina. Relationship to lipofuscin accumulation and macular degeneration,” Investig. Ophthalmol. Vis. Sci. 30, 1691–1699 (1989).

1986 (1)

J. M. Bland and D. G. Altman, “Statistical methods for assessing agreement between two methods of clinical measurement,” Lancet 327, 307–310 (1986).
[CrossRef]

1980 (1)

D. Marr and E. Hildreth, “Theory of edge detection,” Proc. R. Soc. B 207, 187–217 (1980).

1979 (1)

N. Otsu, “A threshold selection method from gray-level histograms,” IEEE Trans. Syst. Man Cybern. 9, 62–66 (1979).
[CrossRef]

1977 (2)

G. W. Zack, W. E. Rogers, and S. A. Latt, “Automatic measurement of sister chromatid exchange frequency,” J. Histochem. Cytochem. 25, 741–753 (1977).
[CrossRef]

H. Wilson and S. Giese, “Threshold visibility of frequency gradient patterns,” Vis. Res. 17, 1177–1190 (1977).
[CrossRef]

1967 (1)

M. O. M. Ts’o and E. Friedman, “The retinal pigment epithelium: I. Comparative histology,” Arch. Ophthalmol. 78, 641–649 (1967).

Ahamd, K.

Altman, D. G.

J. M. Bland and D. G. Altman, “Statistical methods for assessing agreement between two methods of clinical measurement,” Lancet 327, 307–310 (1986).
[CrossRef]

Arora, S. K.

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Baraas, R. C.

Bedoya-Calle, A. H.

J. C. Valencia-Estrada and A. H. Bedoya-Calle, “Trigonometría elíptica para su uso en ingeniería,” in Jornadas de Investigación EIA 2009 (Escuela de Ingeniería de Antioquia, 2009), pp. 84–92.

Beucher, S.

S. Beucher and F. Meyer, “Methodes d’analyse de contrastes a l’analyseur de textures,” Technical report (Ecole des Mines de Paris, Centre de Morphologie Mathématique Fontainebleau, 1977).

Bland, J. M.

J. M. Bland and D. G. Altman, “Statistical methods for assessing agreement between two methods of clinical measurement,” Lancet 327, 307–310 (1986).
[CrossRef]

Bok, D.

D. Bok, “The retinal pigment epithelium: a versatile partner in vision,” J. Cell Sci., Suppl. 17, 189–195 (1993).

Boulton, M.

M. Boulton and P. Dayhaw-Barker, “The role of the retinal pigment epithelium: topographical variation and ageing changes,” Eye 15, 384–389 (2001).
[CrossRef]

Campbell, M.

Carroll, J.

Chiu, S. J.

Choi, S. S.

J. Carroll, S. S. Choi, and D. R. Williams, “In vivo imaging of the photoreceptor mosaic of a rod monochromat,” Vis. Res. 48, 2564–2568 (2008).
[CrossRef]

Chrenek, M. A.

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Chung, M.

Chung, M. M.

E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. Folwell, D. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4, 2527–2539 (2013).
[CrossRef]

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Dayhaw-Barker, P.

M. Boulton and P. Dayhaw-Barker, “The role of the retinal pigment epithelium: topographical variation and ageing changes,” Eye 15, 384–389 (2001).
[CrossRef]

Del Priore, L. V.

L. V. Del Priore, Y.-H. Kuo, and T. H. Tezel, “Age-related changes in human RPE cell density and apoptosis proportion in situ,” Investig. Ophthalmol. Vis. Sci. 43, 3312–3318 (2002).

Delori, F. C.

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

Dorey, C. K.

C. K. Dorey, G. Wu, D. Ebenstein, A. Garsd, and J. J. Weiter, “Cell loss in the aging retina. Relationship to lipofuscin accumulation and macular degeneration,” Investig. Ophthalmol. Vis. Sci. 30, 1691–1699 (1989).

Dubis, A. M.

Dubra, A.

S. J. Chiu, Y. Lokhnygina, A. M. Dubis, A. Dubra, J. Carroll, J. A. Izatt, and S. Farsiu, “Automatic cone photoreceptor segmentation using graph theory and dynamic programming,” Biomed. Opt. Express 4, 924–937 (2013).
[CrossRef]

E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. Folwell, D. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4, 2527–2539 (2013).
[CrossRef]

D. Scoles, Y. N. Sulai, and A. Dubra, “In vivo dark-field imaging of the retinal pigment epithelium cell mosaic,” Biomed. Opt. Express 4, 1710–1723 (2013).
[CrossRef]

Y. N. Sulai and A. Dubra, “Adaptive optics scanning ophthalmoscopy with annular pupils,” Biomed. Opt. Express 3, 1647–1661 (2012).
[CrossRef]

E. A. Rossi, M. Chung, A. Dubra, J. J. Hunter, W. H. Merigan, and D. R. Williams, “Imaging retinal mosaics in the living eye,” Eye 25, 301–308 (2011).
[CrossRef]

A. Dubra and Y. Sulai, “Reflective afocal broadband adaptive optics scanning ophthalmoscope,” Biomed. Opt. Express 2, 1757–1768 (2011).
[CrossRef]

J. J. Hunter, B. Masella, A. Dubra, R. Sharma, L. Yin, W. H. Merigan, G. Palczewska, K. Palczewski, and D. R. Williams, “Images of photoreceptors in living primate eyes using adaptive optics two-photon ophthalmoscopy,” Biomed. Opt. Express 2, 139–148 (2011).
[CrossRef]

J. I. W. Morgan, A. Dubra, R. Wolfe, W. H. Merigan, and D. R. Williams, “In vivo autofluorescence imaging of the human and macaque retinal pigment epithelial cell mosaic,” Investig. Ophthalmol. Vis. Sci. 50, 1350–1359 (2008).
[CrossRef]

D. C. Gray, W. Merigan, J. I. Wolfing, B. P. Gee, J. Porter, A. Dubra, T. H. Twietmeyer, K. Ahamd, R. Tumbar, F. Reinholz, and D. R. Williams, “In vivo fluorescence imaging of primate retinal ganglion cells and retinal pigment epithelial cells,” Opt. Express 14, 7144–7158 (2006).
[CrossRef]

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Duncan, J. L.

A. Roorda, Y. Zhang, and J. L. Duncan, “High-resolution in vivo imaging of the RPE mosaic in eyes with retinal disease,” Investig. Ophthalmol. Vis. Sci. 48, 2297–2303 (2007).
[CrossRef]

Ebenstein, D.

C. K. Dorey, G. Wu, D. Ebenstein, A. Garsd, and J. J. Weiter, “Cell loss in the aging retina. Relationship to lipofuscin accumulation and macular degeneration,” Investig. Ophthalmol. Vis. Sci. 30, 1691–1699 (1989).

Farsiu, S.

Fischer, W.

E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. Folwell, D. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4, 2527–2539 (2013).
[CrossRef]

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Folwell, M.

Folwell, M. A.

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Foster, D. H.

Friedman, E.

M. O. M. Ts’o and E. Friedman, “The retinal pigment epithelium: I. Comparative histology,” Arch. Ophthalmol. 78, 641–649 (1967).

Garsd, A.

C. K. Dorey, G. Wu, D. Ebenstein, A. Garsd, and J. J. Weiter, “Cell loss in the aging retina. Relationship to lipofuscin accumulation and macular degeneration,” Investig. Ophthalmol. Vis. Sci. 30, 1691–1699 (1989).

Gee, B. P.

Giese, S.

H. Wilson and S. Giese, “Threshold visibility of frequency gradient patterns,” Vis. Res. 17, 1177–1190 (1977).
[CrossRef]

Gonzalez, R. C.

R. C. Gonzalez and R. E. Woods, Digital Image Processing (Addison-Wesley, 1993).

Gray, D. C.

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

D. C. Gray, W. Merigan, J. I. Wolfing, B. P. Gee, J. Porter, A. Dubra, T. H. Twietmeyer, K. Ahamd, R. Tumbar, F. Reinholz, and D. R. Williams, “In vivo fluorescence imaging of primate retinal ganglion cells and retinal pigment epithelial cells,” Opt. Express 14, 7144–7158 (2006).
[CrossRef]

Grossniklaus, H. E.

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Gunther, K. L.

Hammer, D. X.

Hebert, T.

Hildreth, E.

D. Marr and E. Hildreth, “Theory of edge detection,” Proc. R. Soc. B 207, 187–217 (1980).

Huang, L.-K.

L.-K. Huang and M.-J. J. Wang, “Image thresholding by minimizing the measures of fuzziness,” Pattern Recogn. 28, 41–51 (1995).
[CrossRef]

Hunter, J. J.

J. J. Hunter, B. Masella, A. Dubra, R. Sharma, L. Yin, W. H. Merigan, G. Palczewska, K. Palczewski, and D. R. Williams, “Images of photoreceptors in living primate eyes using adaptive optics two-photon ophthalmoscopy,” Biomed. Opt. Express 2, 139–148 (2011).
[CrossRef]

E. A. Rossi, M. Chung, A. Dubra, J. J. Hunter, W. H. Merigan, and D. R. Williams, “Imaging retinal mosaics in the living eye,” Eye 25, 301–308 (2011).
[CrossRef]

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

Izatt, J. A.

Kay, P.

P. Kay, Y. Yang, and L. Paraoan, “Directional protein secretion by the retinal pigment epithelium: roles in retinal health and the development of age-related macular degeneration,” J. Cell. Mol. Med. 17, 833–843 (2013).

Kuo, Y.-H.

L. V. Del Priore, Y.-H. Kuo, and T. H. Tezel, “Age-related changes in human RPE cell density and apoptosis proportion in situ,” Investig. Ophthalmol. Vis. Sci. 43, 3312–3318 (2002).

Latchney, L. R.

E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. Folwell, D. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4, 2527–2539 (2013).
[CrossRef]

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Latt, S. A.

G. W. Zack, W. E. Rogers, and S. A. Latt, “Automatic measurement of sister chromatid exchange frequency,” J. Histochem. Cytochem. 25, 741–753 (1977).
[CrossRef]

Leung, I. Y.-F.

D. M. Snodderly, M. M. Sandstrom, I. Y.-F. Leung, C. L. Zucker, and M. Neuringer, “Retinal pigment epithelial cell distribution in central retina of rhesus monkeys,” Investig. Ophthalmol. Vis. Sci. 43, 2815–2818 (2002).

Li, K. Y.

Liang, J.

J. Liang, D. R. Williams, and D. T. Miller, “Supernormal vision and high-resolution retinal imaging through adaptive optics,” J. Opt. Soc. Am. A 14, 2884–2892 (1997).
[CrossRef]

D. T. Miller, D. R. Williams, G. M. Morris, and J. Liang, “Images of cone photoreceptors in the living human eye,” Vis. Res. 36, 1067–1079 (1996).
[CrossRef]

Lokhnygina, Y.

Marr, D.

D. Marr and E. Hildreth, “Theory of edge detection,” Proc. R. Soc. B 207, 187–217 (1980).

Masella, B.

J. J. Hunter, B. Masella, A. Dubra, R. Sharma, L. Yin, W. H. Merigan, G. Palczewska, K. Palczewski, and D. R. Williams, “Images of photoreceptors in living primate eyes using adaptive optics two-photon ophthalmoscopy,” Biomed. Opt. Express 2, 139–148 (2011).
[CrossRef]

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

Merigan, W.

Merigan, W. H.

J. J. Hunter, B. Masella, A. Dubra, R. Sharma, L. Yin, W. H. Merigan, G. Palczewska, K. Palczewski, and D. R. Williams, “Images of photoreceptors in living primate eyes using adaptive optics two-photon ophthalmoscopy,” Biomed. Opt. Express 2, 139–148 (2011).
[CrossRef]

E. A. Rossi, M. Chung, A. Dubra, J. J. Hunter, W. H. Merigan, and D. R. Williams, “Imaging retinal mosaics in the living eye,” Eye 25, 301–308 (2011).
[CrossRef]

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

J. I. W. Morgan, A. Dubra, R. Wolfe, W. H. Merigan, and D. R. Williams, “In vivo autofluorescence imaging of the human and macaque retinal pigment epithelial cell mosaic,” Investig. Ophthalmol. Vis. Sci. 50, 1350–1359 (2008).
[CrossRef]

Merino, D.

Meyer, F.

S. Beucher and F. Meyer, “Methodes d’analyse de contrastes a l’analyseur de textures,” Technical report (Ecole des Mines de Paris, Centre de Morphologie Mathématique Fontainebleau, 1977).

Miller, D. T.

J. Liang, D. R. Williams, and D. T. Miller, “Supernormal vision and high-resolution retinal imaging through adaptive optics,” J. Opt. Soc. Am. A 14, 2884–2892 (1997).
[CrossRef]

D. T. Miller, D. R. Williams, G. M. Morris, and J. Liang, “Images of cone photoreceptors in the living human eye,” Vis. Res. 36, 1067–1079 (1996).
[CrossRef]

Morgan, J. I. W.

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

J. I. W. Morgan, A. Dubra, R. Wolfe, W. H. Merigan, and D. R. Williams, “In vivo autofluorescence imaging of the human and macaque retinal pigment epithelial cell mosaic,” Investig. Ophthalmol. Vis. Sci. 50, 1350–1359 (2008).
[CrossRef]

J. I. W. Morgan, Department of Ophthalmology, University of Pennsylvania, 3400 Civic Center Blvd., Ophthalmology 3rd floor WEST 3–113W, Philadelphia, Pennsylvania 19104–6100 (personal communication, 2013).

Morris, G. M.

D. T. Miller, D. R. Williams, G. M. Morris, and J. Liang, “Images of cone photoreceptors in the living human eye,” Vis. Res. 36, 1067–1079 (1996).
[CrossRef]

Neitz, M.

Neuringer, M.

D. M. Snodderly, M. M. Sandstrom, I. Y.-F. Leung, C. L. Zucker, and M. Neuringer, “Retinal pigment epithelial cell distribution in central retina of rhesus monkeys,” Investig. Ophthalmol. Vis. Sci. 43, 2815–2818 (2002).

Nickerson, J. M.

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Otsu, N.

N. Otsu, “A threshold selection method from gray-level histograms,” IEEE Trans. Syst. Man Cybern. 9, 62–66 (1979).
[CrossRef]

Palczewska, G.

Palczewski, K.

Paraoan, L.

P. Kay, Y. Yang, and L. Paraoan, “Directional protein secretion by the retinal pigment epithelium: roles in retinal health and the development of age-related macular degeneration,” J. Cell. Mol. Med. 17, 833–843 (2013).

Park, S.

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Parkins, K.

Porter, J.

Putnam, N. M.

Queener, H.

Rangel-Fonseca, P.

Rashid, A.

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Reinholz, F.

Rickman, C. B.

Rogers, W. E.

G. W. Zack, W. E. Rogers, and S. A. Latt, “Automatic measurement of sister chromatid exchange frequency,” J. Histochem. Cytochem. 25, 741–753 (1977).
[CrossRef]

Romero-Borja, F.

Roorda, A.

Rossi, E. A.

E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. Folwell, D. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4, 2527–2539 (2013).
[CrossRef]

E. A. Rossi, M. Chung, A. Dubra, J. J. Hunter, W. H. Merigan, and D. R. Williams, “Imaging retinal mosaics in the living eye,” Eye 25, 301–308 (2011).
[CrossRef]

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Russ, J. C.

J. C. Russ, The Image Processing Handbook (CRC Press, 2002).

Sandstrom, M. M.

D. M. Snodderly, M. M. Sandstrom, I. Y.-F. Leung, C. L. Zucker, and M. Neuringer, “Retinal pigment epithelial cell distribution in central retina of rhesus monkeys,” Investig. Ophthalmol. Vis. Sci. 43, 2815–2818 (2002).

Scoles, D.

Serra, J. P.

J. P. Serra, Image Analysis and Mathematical Morphology (Academic, 1982).

Sharma, R.

Snodderly, D. M.

D. M. Snodderly, M. M. Sandstrom, I. Y.-F. Leung, C. L. Zucker, and M. Neuringer, “Retinal pigment epithelial cell distribution in central retina of rhesus monkeys,” Investig. Ophthalmol. Vis. Sci. 43, 2815–2818 (2002).

Song, H.

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Strauss, O.

O. Strauss, “The retinal pigment epithelium in visual function,” Physiol. Rev. 85, 845–881 (2005).
[CrossRef]

Sulai, Y.

Sulai, Y. N.

Tezel, T. H.

L. V. Del Priore, Y.-H. Kuo, and T. H. Tezel, “Age-related changes in human RPE cell density and apoptosis proportion in situ,” Investig. Ophthalmol. Vis. Sci. 43, 3312–3318 (2002).

Toth, C. A.

Ts’o, M. O. M.

M. O. M. Ts’o and E. Friedman, “The retinal pigment epithelium: I. Comparative histology,” Arch. Ophthalmol. 78, 641–649 (1967).

Tumbar, R.

Twietmeyer, T. H.

Valencia-Estrada, J. C.

J. C. Valencia-Estrada and A. H. Bedoya-Calle, “Trigonometría elíptica para su uso en ingeniería,” in Jornadas de Investigación EIA 2009 (Escuela de Ingeniería de Antioquia, 2009), pp. 84–92.

Wang, M.-J. J.

L.-K. Huang and M.-J. J. Wang, “Image thresholding by minimizing the measures of fuzziness,” Pattern Recogn. 28, 41–51 (1995).
[CrossRef]

Weiter, J. J.

C. K. Dorey, G. Wu, D. Ebenstein, A. Garsd, and J. J. Weiter, “Cell loss in the aging retina. Relationship to lipofuscin accumulation and macular degeneration,” Investig. Ophthalmol. Vis. Sci. 30, 1691–1699 (1989).

William Donnelly, I.

Williams, D.

Williams, D. R.

E. A. Rossi, M. Chung, A. Dubra, J. J. Hunter, W. H. Merigan, and D. R. Williams, “Imaging retinal mosaics in the living eye,” Eye 25, 301–308 (2011).
[CrossRef]

D. R. Williams, “Imaging single cells in the living retina,” Vis. Res. 51, 1379–1396 (2011).
[CrossRef]

J. J. Hunter, B. Masella, A. Dubra, R. Sharma, L. Yin, W. H. Merigan, G. Palczewska, K. Palczewski, and D. R. Williams, “Images of photoreceptors in living primate eyes using adaptive optics two-photon ophthalmoscopy,” Biomed. Opt. Express 2, 139–148 (2011).
[CrossRef]

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

J. Carroll, S. S. Choi, and D. R. Williams, “In vivo imaging of the photoreceptor mosaic of a rod monochromat,” Vis. Res. 48, 2564–2568 (2008).
[CrossRef]

J. I. W. Morgan, A. Dubra, R. Wolfe, W. H. Merigan, and D. R. Williams, “In vivo autofluorescence imaging of the human and macaque retinal pigment epithelial cell mosaic,” Investig. Ophthalmol. Vis. Sci. 50, 1350–1359 (2008).
[CrossRef]

R. C. Baraas, J. Carroll, K. L. Gunther, M. Chung, D. R. Williams, D. H. Foster, and M. Neitz, “Adaptive optics retinal imaging reveals s-cone dystrophy in tritan color-vision deficiency,” J. Opt. Soc. Am. A 24, 1438–1447 (2007).
[CrossRef]

D. C. Gray, W. Merigan, J. I. Wolfing, B. P. Gee, J. Porter, A. Dubra, T. H. Twietmeyer, K. Ahamd, R. Tumbar, F. Reinholz, and D. R. Williams, “In vivo fluorescence imaging of primate retinal ganglion cells and retinal pigment epithelial cells,” Opt. Express 14, 7144–7158 (2006).
[CrossRef]

J. Liang, D. R. Williams, and D. T. Miller, “Supernormal vision and high-resolution retinal imaging through adaptive optics,” J. Opt. Soc. Am. A 14, 2884–2892 (1997).
[CrossRef]

D. T. Miller, D. R. Williams, G. M. Morris, and J. Liang, “Images of cone photoreceptors in the living human eye,” Vis. Res. 36, 1067–1079 (1996).
[CrossRef]

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Wilson, H.

H. Wilson and S. Giese, “Threshold visibility of frequency gradient patterns,” Vis. Res. 17, 1177–1190 (1977).
[CrossRef]

Wolfe, R.

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

J. I. W. Morgan, A. Dubra, R. Wolfe, W. H. Merigan, and D. R. Williams, “In vivo autofluorescence imaging of the human and macaque retinal pigment epithelial cell mosaic,” Investig. Ophthalmol. Vis. Sci. 50, 1350–1359 (2008).
[CrossRef]

Wolfing, J. I.

Woods, R. E.

R. C. Gonzalez and R. E. Woods, Digital Image Processing (Addison-Wesley, 1993).

Wu, G.

C. K. Dorey, G. Wu, D. Ebenstein, A. Garsd, and J. J. Weiter, “Cell loss in the aging retina. Relationship to lipofuscin accumulation and macular degeneration,” Investig. Ophthalmol. Vis. Sci. 30, 1691–1699 (1989).

Yang, Y.

P. Kay, Y. Yang, and L. Paraoan, “Directional protein secretion by the retinal pigment epithelium: roles in retinal health and the development of age-related macular degeneration,” J. Cell. Mol. Med. 17, 833–843 (2013).

Yin, L.

Zack, G. W.

G. W. Zack, W. E. Rogers, and S. A. Latt, “Automatic measurement of sister chromatid exchange frequency,” J. Histochem. Cytochem. 25, 741–753 (1977).
[CrossRef]

Zhang, Q.

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

Zhang, Y.

N. M. Putnam, D. X. Hammer, Y. Zhang, D. Merino, and A. Roorda, “Modeling the foveal cone mosaic imaged with adaptive optics scanning laser ophthalmoscopy,” Opt. Express 18, 24902–24916 (2010).
[CrossRef]

A. Roorda, Y. Zhang, and J. L. Duncan, “High-resolution in vivo imaging of the RPE mosaic in eyes with retinal disease,” Investig. Ophthalmol. Vis. Sci. 48, 2297–2303 (2007).
[CrossRef]

Zucker, C. L.

D. M. Snodderly, M. M. Sandstrom, I. Y.-F. Leung, C. L. Zucker, and M. Neuringer, “Retinal pigment epithelial cell distribution in central retina of rhesus monkeys,” Investig. Ophthalmol. Vis. Sci. 43, 2815–2818 (2002).

Arch. Ophthalmol. (1)

M. O. M. Ts’o and E. Friedman, “The retinal pigment epithelium: I. Comparative histology,” Arch. Ophthalmol. 78, 641–649 (1967).

Biomed. Opt. Express (7)

E. A. Rossi, P. Rangel-Fonseca, K. Parkins, W. Fischer, L. R. Latchney, M. Folwell, D. Williams, A. Dubra, and M. M. Chung, “In vivo imaging of retinal pigment epithelium cells in age related macular degeneration,” Biomed. Opt. Express 4, 2527–2539 (2013).
[CrossRef]

D. Scoles, Y. N. Sulai, and A. Dubra, “In vivo dark-field imaging of the retinal pigment epithelium cell mosaic,” Biomed. Opt. Express 4, 1710–1723 (2013).
[CrossRef]

S. J. Chiu, C. A. Toth, C. B. Rickman, J. A. Izatt, and S. Farsiu, “Automatic segmentation of closed-contour features in ophthalmic images using graph theory and dynamic programming,” Biomed. Opt. Express 3, 1127–1140 (2012).
[CrossRef]

S. J. Chiu, Y. Lokhnygina, A. M. Dubis, A. Dubra, J. Carroll, J. A. Izatt, and S. Farsiu, “Automatic cone photoreceptor segmentation using graph theory and dynamic programming,” Biomed. Opt. Express 4, 924–937 (2013).
[CrossRef]

Y. N. Sulai and A. Dubra, “Adaptive optics scanning ophthalmoscopy with annular pupils,” Biomed. Opt. Express 3, 1647–1661 (2012).
[CrossRef]

J. J. Hunter, B. Masella, A. Dubra, R. Sharma, L. Yin, W. H. Merigan, G. Palczewska, K. Palczewski, and D. R. Williams, “Images of photoreceptors in living primate eyes using adaptive optics two-photon ophthalmoscopy,” Biomed. Opt. Express 2, 139–148 (2011).
[CrossRef]

A. Dubra and Y. Sulai, “Reflective afocal broadband adaptive optics scanning ophthalmoscope,” Biomed. Opt. Express 2, 1757–1768 (2011).
[CrossRef]

Eye (2)

E. A. Rossi, M. Chung, A. Dubra, J. J. Hunter, W. H. Merigan, and D. R. Williams, “Imaging retinal mosaics in the living eye,” Eye 25, 301–308 (2011).
[CrossRef]

M. Boulton and P. Dayhaw-Barker, “The role of the retinal pigment epithelium: topographical variation and ageing changes,” Eye 15, 384–389 (2001).
[CrossRef]

IEEE Trans. Syst. Man Cybern. (1)

N. Otsu, “A threshold selection method from gray-level histograms,” IEEE Trans. Syst. Man Cybern. 9, 62–66 (1979).
[CrossRef]

Investig. Ophthalmol. Vis. Sci. (6)

D. M. Snodderly, M. M. Sandstrom, I. Y.-F. Leung, C. L. Zucker, and M. Neuringer, “Retinal pigment epithelial cell distribution in central retina of rhesus monkeys,” Investig. Ophthalmol. Vis. Sci. 43, 2815–2818 (2002).

C. K. Dorey, G. Wu, D. Ebenstein, A. Garsd, and J. J. Weiter, “Cell loss in the aging retina. Relationship to lipofuscin accumulation and macular degeneration,” Investig. Ophthalmol. Vis. Sci. 30, 1691–1699 (1989).

L. V. Del Priore, Y.-H. Kuo, and T. H. Tezel, “Age-related changes in human RPE cell density and apoptosis proportion in situ,” Investig. Ophthalmol. Vis. Sci. 43, 3312–3318 (2002).

J. I. W. Morgan, J. J. Hunter, B. Masella, R. Wolfe, D. C. Gray, W. H. Merigan, F. C. Delori, and D. R. Williams, “Light-induced retinal changes observed with high-resolution autofluorescence imaging of the retinal pigment epithelium,” Investig. Ophthalmol. Vis. Sci. 49, 3715–3729 (2008).
[CrossRef]

J. I. W. Morgan, A. Dubra, R. Wolfe, W. H. Merigan, and D. R. Williams, “In vivo autofluorescence imaging of the human and macaque retinal pigment epithelial cell mosaic,” Investig. Ophthalmol. Vis. Sci. 50, 1350–1359 (2008).
[CrossRef]

A. Roorda, Y. Zhang, and J. L. Duncan, “High-resolution in vivo imaging of the RPE mosaic in eyes with retinal disease,” Investig. Ophthalmol. Vis. Sci. 48, 2297–2303 (2007).
[CrossRef]

J. Cell Sci., Suppl. (1)

D. Bok, “The retinal pigment epithelium: a versatile partner in vision,” J. Cell Sci., Suppl. 17, 189–195 (1993).

J. Cell. Mol. Med. (1)

P. Kay, Y. Yang, and L. Paraoan, “Directional protein secretion by the retinal pigment epithelium: roles in retinal health and the development of age-related macular degeneration,” J. Cell. Mol. Med. 17, 833–843 (2013).

J. Histochem. Cytochem. (1)

G. W. Zack, W. E. Rogers, and S. A. Latt, “Automatic measurement of sister chromatid exchange frequency,” J. Histochem. Cytochem. 25, 741–753 (1977).
[CrossRef]

J. Opt. Soc. Am. A (3)

Lancet (1)

J. M. Bland and D. G. Altman, “Statistical methods for assessing agreement between two methods of clinical measurement,” Lancet 327, 307–310 (1986).
[CrossRef]

Opt. Express (3)

Pattern Recogn. (1)

L.-K. Huang and M.-J. J. Wang, “Image thresholding by minimizing the measures of fuzziness,” Pattern Recogn. 28, 41–51 (1995).
[CrossRef]

Physiol. Rev. (1)

O. Strauss, “The retinal pigment epithelium in visual function,” Physiol. Rev. 85, 845–881 (2005).
[CrossRef]

Proc. R. Soc. B (1)

D. Marr and E. Hildreth, “Theory of edge detection,” Proc. R. Soc. B 207, 187–217 (1980).

Vis. Res. (4)

H. Wilson and S. Giese, “Threshold visibility of frequency gradient patterns,” Vis. Res. 17, 1177–1190 (1977).
[CrossRef]

D. T. Miller, D. R. Williams, G. M. Morris, and J. Liang, “Images of cone photoreceptors in the living human eye,” Vis. Res. 36, 1067–1079 (1996).
[CrossRef]

J. Carroll, S. S. Choi, and D. R. Williams, “In vivo imaging of the photoreceptor mosaic of a rod monochromat,” Vis. Res. 48, 2564–2568 (2008).
[CrossRef]

D. R. Williams, “Imaging single cells in the living retina,” Vis. Res. 51, 1379–1396 (2011).
[CrossRef]

Other (9)

A. Rashid, S. K. Arora, M. A. Chrenek, S. Park, Q. Zhang, J. M. Nickerson, and H. E. Grossniklaus, “Spatial analysis of morphometry of retinal pigment epithelium in the normal human eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

E. A. Rossi, D. R. Williams, A. Dubra, L. R. Latchney, M. A. Folwell, W. Fischer, H. Song, and M. M. Chung, “Individual retinal pigment epithelium cells can be imaged in vivo in age related macular degeneration,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

S. Beucher and F. Meyer, “Methodes d’analyse de contrastes a l’analyseur de textures,” Technical report (Ecole des Mines de Paris, Centre de Morphologie Mathématique Fontainebleau, 1977).

R. C. Gonzalez and R. E. Woods, Digital Image Processing (Addison-Wesley, 1993).

J. C. Russ, The Image Processing Handbook (CRC Press, 2002).

J. P. Serra, Image Analysis and Mathematical Morphology (Academic, 1982).

S. K. Arora, A. Rashid, M. A. Chrenek, Q. Zhang, S. Park, H. E. Grossniklaus, and J. M. Nickerson, “Analysis of human retinal pigment epithelium (RPE) morphometry in the macula of the normal aging eye,” presented at ARVO 2013 Annual Meeting, Seattle, Washington, 2013.

J. C. Valencia-Estrada and A. H. Bedoya-Calle, “Trigonometría elíptica para su uso en ingeniería,” in Jornadas de Investigación EIA 2009 (Escuela de Ingeniería de Antioquia, 2009), pp. 84–92.

J. I. W. Morgan, Department of Ophthalmology, University of Pennsylvania, 3400 Civic Center Blvd., Ophthalmology 3rd floor WEST 3–113W, Philadelphia, Pennsylvania 19104–6100 (personal communication, 2013).

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Figures (9)

Fig. 1.
Fig. 1.

Schematic representation of the algorithm.

Fig. 2.
Fig. 2.

Kernels used in the algorithm: (a) mean circular filter, (b) structuring element for erosion, (c) Mexican-hat Kernel, and (d) structuring element for edge correction.

Fig. 3.
Fig. 3.

Stages of the algorithm, human image: (a) original, (b) smoothing, (c) erosion, (d) edge detection, (e) edge correction, (f) binarization, and (g) shrinking. Scale bar: 50 μm.

Fig. 4.
Fig. 4.

Synthetic images (top row), corresponding segmentation images (middle row), and cell area histograms (bottom row). Histograms were generated from the cell areas computed from the segmentation images. (a), (d), (g) White noise, (b), (e), (h) hexagonal array, and (c), (f), (i) hexagonal array with SNR=5db. The pseudocells’ diameters are between 12 and 24 pixels.

Fig. 5.
Fig. 5.

RPE cells mosaic and corresponding segmentation: (a), (e) Monkey 526 at approximately 10° nasal-superior, (b), (f) monkey 320 at fovea, (c), (g) human at approximately 6.75° superior and 2.5° temporal, and (d), (h) human at approximately 1.75° superior and 10° temporal. Scale bar: 50 μm.

Fig. 6.
Fig. 6.

Macaque RPE cells mosaic and corresponding segmentation at approximately 2° temporal, 7° superior: (a), (d) time point 1; (b), (e) time point 2; (c), (f) time point 3. Scale bar: 50 μm.

Fig. 7.
Fig. 7.

Macaque RPE cells mosaic at different exposures and corresponding segmentation at approximately 2° temporal, 9° superior: (a), (g) 5 μW, (b), (h) 12 μW, (c), (i) 16 μW, (d), (j) 20 μW, (e), (k) 30 μW, and (f), (l) 47 μW. Scale bar: 50 μm.

Fig. 8.
Fig. 8.

Bland–Altman plot shows that there is an absolute systematic error between the proposed algorithm and manual cell identification. This is due to the fact that the human can infer the presence of two or more cells when their borders are indistinct or absent, but the algorithm cannot.

Fig. 9.
Fig. 9.

Comparison of cells segmentation using Voronoi diagram and the proposed algorithm. (a) Simulated RPE mosaic supposing lost cells in red, (b) centroids from (a), (c) Voronoi diagram from (b), (d) simulated mosaic with lost cells, (e) segmentation from (d) using proposed algorithm, (f) simulated RPE mosaic surrounded by several lost cells, (g) centroids from (f), (h) Voronoi diagram from (g), and (i) segmentation from (f) using proposed algorithm. Magenta, blue, green, yellow, and red synthetic cells have 4, 5, 6, 7, and 8 Voronoi neighbors, respectively.

Tables (2)

Tables Icon

Table 1. Comparison of Algorithmic Segmentation and Manual Counting of RPE Cells in Monkey 320 from Morgan et al. [6]

Tables Icon

Table 2. Statistics of RPE Cells from Monkey 526 in Figs. 6 and 7

Equations (1)

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g(x,y)={1f(x,y)10f(x,y)<1.

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